Common Agency with Horizontally Differentiated Principals
分析了一个代理人对两个委托人价值不同的私有信息下的共同代理关系。委托人独立提供激励合同时，代理人专业化程度低于社会最优但高于合作情形；合作时固定费用区域更大、激励强度更低。委托人偏好独立签约而非排他性交易。
I analyze a common agency relationship where the agent has private information about the difference in his value for two principals. When the principals independently offer incentive contracts, the agent specializes less than is socially efficient, but more than when they cooperate and choose the contract that maximizes their joint payoff. Under both arrangements the agent faces countervailing incentives. The pooling region of types receiving a flat fee is larger and the incentive pay of the remaining types is lower powered under cooperation than under independent contracting. The principals prefer independent contracting with a common agent to exclusive dealing.